Optional but recommended: Rinse the shrimp shells under cold running water. Heat a saucepan over medium heat and add a drizzle of olive oil. When oil is hot, add the shrimp SHELLS (not the shrimp!) and toss for 30 seconds in the hot oil. Add the wine or broth and bring to a boil. Lower the heat and simmer for 5 minutes. After five minutes, strain the wine or broth for use. I had about 7/8 of the cup of liquid left after simmering.

In a large skillet with a lid, melt the butter with olive oil over medium heat. Add the garlic and cook until fragrant, about 30 seconds. Add the wine or broth, salt, red pepper flakes, and lots of black pepper and bring to a simmer. Let wine or broth reduce by half, about 3-4 minutes.

Add the shrimp into the liquid and spread them out in an even layer, then cover the pan. Cook, stirring occasionally, until the shrimp just turn pink and have curled up into a loose "C" shape ("C" stands for "cooked," "O" stands for "overcooked"), 2 to 4 minutes depending upon their size. Stir in the parsley and lemon juice. Toss with pasta or serve with crusty bread.

A slightly fussier step for serving with pasta: Try the following and you'll have silkier, thicker sauce.

First, DON'T add the parsley and lemon juice yet - cooked lemon juice can get a bit weird.

About a minute before both the shrimp and the pasta are done, ladle the pasta water into the sauce. Add the pasta and toss, continuing to cook everything over medium-low heat, about 1-2 minutes, until everything is combined and the sauce has thickened. Add parsley and lemon juice and toss to combine.